437 research outputs found

    A New Route for Preparation of 2-Deoxy-D-ribofuranose Phospho Sugar

    Get PDF
    The addition reaction of dimethyl phosphonate to (2R,4S)-4-(tertbutyldimethylsilyl)oxymethyl-2-methyl-1,3-dioxan-5-one (11a), followed by dehydroxylation, provided 1-O-(tert-butyldimethylsilyl)-3-deoxy-3-dimethoxyphosphinoyl-2,4-O-ethylidene-D-erythritol (13a). Elongation of carbon skeleton of the D-erythrose (14) derived from 13a and then acidic methanolysis gave a mixture of methyl 2,4-dideoxy-4-dimethoxyphosphinoyl-alpha,beta-D-erythropentopyranosides (7), which was led to 2-deoxy-D-ribofuranose phospho sugar (4) in an appreciably improved total yield compared with the procedures via previously reported route

    Longevity-associated NADH Dehydrogenase Subunit-2 237 Leu/Met Polymorphism Modulates the Effects of Daily Alcohol Drinking on Yearly Changes in Serum Total and LDL Cholesterol in Japanese Men

    Get PDF
    Reduced nicotinamide adenine dinucleotide (NADH) dehydrogenase subunit 2 237 leucine/methionine (ND2-237 Leu/Met) polymorphism, is reportedly associated with longevity in the Japanese population. The ND2-237Met genotype may exert resistance to atherogenic diseases, such as myocardial infarction or cerebrovascular disorders. To investigate whether ND2-237 Leu/Met polymorphism is associated with yearly changes in serum lipid levels, we conducted a longitudinal study of 107 healthy Japanese male subjects. Analysis of covariance revealed that the interaction between the ND2-237 Leu/Met genotypes and habitual drinking was significantly associated with yearly changes in serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDLC) levels (p0.036 and p0.006, respectively). In multiple regression analysis, daily drinking was significantly and positively associated with yearly changes in serum LDLC levels in men with ND2-237Met (p0.026). After adjusting for covariates, yearly changes in serum LDLC levels were significantly lower in non-daily drinkers with ND2-237Met than in those with ND2-237Leu (p0.047). These results suggest that ND2-237Met has a beneficial impact on yearly changes in serum LDLC in non-daily drinkers but not in daily drinkers.</p

    Short or Irregular Sleep Duration in Early Childhood Increases Risk of Injury for Primary School-Age Children: A Nationwide Longitudinal Birth Cohort in Japan

    Get PDF
    The aim of this study was to investigate the longitudinal relationship between shorter or irregular sleep duration (SD) in early childhood and increased risk of injury at primary school age using data from a nationwide survey in Japan. We categorized SD into seven groups: 6 h, 7 h, 8 h, 9 hrs, 10 or 11 h, >12 h, and irregular, based on questionnaire responses collected at 5.5 years old. The relationship between SD and incidence of injury at 5.5-nine years of age is shown. In addition, we completed a stratified analysis on children with or without problematic behavior at eight years old. We included 32,044 children, of which 6369 were classified as having an injury and 25,675 as not having an injury. Logistic regression model showed that shorter or irregular SD categories were associated with an increased adjusted odds ratio (aOR) for injuries (6 h: aOR 1.40, 95% confidence interval (CI) 1.19-1.66, 7 h: aOR 1.10, 95% CI, 0.98-1.23, 8 h: aOR 1.13, 95% CI, 1.02-1.26, irregular: aOR 1.26, 95% CI 1.10-1.43). The same tendency was observed with shorter or irregular SD in subgroups with or without behavioral problems. Shorter or irregular sleep habits during early childhood are associated with injury during primary school age

    SiO Emission in the Multi-Lobe Outflow associated with IRAS 16293-2422

    Get PDF
    We have mapped the thermal emission line of SiO (v = 0; J = 2-1) associated with the quadrupolar molecular outflow driven by the very cold far-infrared source IRAS 16293-2422. The SiO emission is significantly enhanced in the northeastern red lobe and at the position ~50" east of the IRAS source. Strong SiO emission observed at ~50" east of the IRAS source presents evidence for a dynamical interaction between a part of the eastern blue lobe and the dense ambient gas condensation, however, such an interaction is unlikely to be responsible for producing the quadrupolar morphology. The SiO emission in the northeastern red lobe shows the spatial and velocity structure similar to those of the CO outflow, suggesting that the SiO emission comes from the molecular outflow in the northeastern red lobe itself. The observed velocity structure is reproduced by a simple spatio-kinematic model of bow shock with a shock velocity of 19-24 km/s inclined by 30-45 deg from the plane of the sky. This implies that the northeastern red lobe is independent of the eastern blue lobe and that the quadrupolar structure is due to two separate bipolar outflows. The SiO emission observed in the western red lobe has a broad pedestal shape with low intensity. Unlike the SiO emission in the northeastern red lobe, the spatial extent of the SiO emission in the western red lobe is restricted to its central region. The spatial and velocity structures and the line profiles suggest that three different types of the SiO emission are observed in this outflow; the SiO emission arises from the interface between the outflowing gas and the dense ambient gas clump, the SiO emission coming from the outflow lobe itself, and the broad SiO emission with low intensity observed at the central region of the outflow lobe.Comment: 14 pages, 6 figures (figures 1 and 4 are color), gzipped tar file, To appear in the Ap

    Enantioselective synthesis of stimulus-responsive amino acid via asymmetric α-amination of aldehyde

    Get PDF
    Development of a methodology to control the function of peptides and proteins is an indispensable task in the field of chemical biology and drug delivery. Recently, we reported synthesis of racemic stimulus-responsive amino acids and their application for controlling peptidyl function. In this study, we report enantioselective synthesis of a key intermediate of stimulus-responsive amino acids via asymmetric α-amination reaction of an aldehyde. The obtained chiral intermediate was converted to an Fmoc protected UV-responsive amino acid with (S)-configuration, and it was successfully incorporated into a model peptide by Fmoc solid phase peptide synthesis

    The ortho-to-para ratio of ammonia in the L1157 outflow

    Get PDF
    We have measured the ortho-to-para ratio of ammonia in the blueshifted gas of the L1157 outflow by observing the six metastable inversion lines from (J, K) = (1, 1) to (6, 6). The highly excited (5, 5) and (6, 6) lines were first detected in the low-mass star forming regions. The rotational temperature derived from the ratio of four transition lines from (3, 3) to (6, 6) is 130-140 K, suggesting that the blueshifted gas is heated by a factor of ~10 as compared to the quiescent gas. The ortho-to-para ratio of the NH3 molecules in the blueshifted gas is estimated to be 1.3--1.7, which is higher than the statistical equilibrium value. This ratio provides us with evidence that the NH3 molecules have been evaporated from dust grains with the formation temperature between 18 and 25 K. It is most likely that the NH3 molecules on dust grains have been released into the gas phase through the passage of strong shock waves produced by the outflow. Such a scenario is supported by the fact that the ammonia abundance in the blueshifted gas is enhanced by a factor of ~5 with respect to the dense quiescent gas.Comment: 16 pages, including 3 PS figures. To appear in the ApJ (Letters). aastex macro
    corecore